Carbon nanotubes (CNTs) and boron nitride nanotubes (BNNTs) have similar surface crystallography and mechanical properties. It is now shown that the interlayer sliding friction in multilayer CNTs and BNNTs is, however, different: whereas the telescopic sliding of semi-metallic multiwalled CNTs is known to be vanishingly small, multiwalled insulating BNNTs exhibit ultrahigh interlayer friction that is proportional to the contact area—a result ascribed to the ionic character of boron nitride.
- A. Niguès
- A. Siria
- L. Bocquet